I have an 84 L69 305 H.O. and need new valve seals. What size do I need and any recommendations for brands?

 

I'm rebuilding a set of 416 heads, and I'm considering using Fel-Pro INTAKE valve seals on ALL my valves.
There's a difference between the intakes, and the exhausts.
The intakes are a "positive retention" type seal, with a metal band(s) around the outside of the rubber seal. These seals sit securly on the top of the valve guide, without moving.
The common exhaust seals are the umbrella-type, with no type of retention. Therefore, they ride up and down, with the movement of the valve. I've heard that it's a lot easier to eat a valve seal in the valve spring accidentally on the exhaust because the seals move with the valve.
The intake seals also come with little o-rings, for the lower ring in the valve stem. A little extra protection.
Maybe somebody will tell us why using all intake seals is a bad idea?


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No guts, no glory.

 

The only reason I know not to use them is the exhaust stem gets very hot compared to the intake and a little extra oil helps. Being as the exhaust pushes out of the cylinder you don't get the oil sucked in and burnt as you would on an intake valve.
I have heard of guys having no seals on the exhaust and it no causing an oil burning problem although I am not saying that is a good idea.
Bob

 

yes, the exh. valve gets alot hotter then the intake. so the intake is rubber to seal better and the exh. is plastic so it can last. if you put int. seals on exh, it will take too much oil off the valves causeing them to overheat and will just burn up the rubber seal since its too hot. your gm dealer has these seals cause they use them on replacement seal jobs cause they work better. you need the tool that press's them onto the valve guide too. or perhaps a long socket the right size will work to press them on.

have fun


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1985 Iroc Z, (parting out, email for parts)

1986 Iroc Z, (up and running, but still lots of work to do)
355, ported camel hump heads,750 holley, 700r4, 10.5 compr., forged flat tops, solid cam .501I .510E, 4gen rear w/3:73posi,girdle, and disc's, Edel. torker II, shift kit, 3500 stal, hedmann LT. headers, 4 gen seats, man. strg., lt1 starter, alum. w/p, msd :6al, coil, dist., mallory wires. exp high 12's-low 13's

1995 z28,SS Hood, Iroc style spoiler, tints and black outs, 700r4,2400 act. stall speed,B&M hammer shifter, 17" budnick trilogy III wheels, 275/40 ZR17, 160 stat, man. cooling fan sw., homemaid CAI,1LE elbow, hypertech airfoil, t.b.bypass,!cat, flowmaster, !maf screen, relocated batt., 1LE front l.c.a.s', poly trans and torq.arm bushings, MSD 6AL, custom program, p&p maf, accel coil, and under drive pulley

mods that i have, just not on car yet:
msd wires, edelbrock mid. headers, edelbrock rpm catback